Bourbon barrel-aged imperial stout. Rum barrel-aged quad. Blackberry sour ale aged in pinot noir barrels. None of these sound particularly exotic to serious beer drinkers, but most of today's barrel-aged beers are a recent development. In fact, the history — and purpose — of barrel-aging beer remains a mystery to many of the people who enjoy them.
As I sat in Russian River Brewing Company's legendary Santa Rosa, Calif., brewpub last week, I wondered how many people truly appreciate the role that barrel-aging contributes to many of the beers they love. I was drinking Beatification, a spontaneously fermented sour ale aged in wine barrels. Although the technique was inspired by traditional Belgian lambic ales like Cantillon, domestic representations of the process didn't exist prior to this millennium.
It was 1999 when Russian River's Vinnie Cilurzo started playing around with wild yeast and Belgian-style barrel aging. The resulting beer (released a couple of years later) was Temptation, a sour blonde ale aged in local Chardonnay barrels. In 2000, Tomme Arthur of San Marcos' Lost Abbey Brewing (Pizza Port Brewing at the time) released Cuvee de Tomme — a sour brown ale aged in Bourbon barrels, with raisins and sour cherries added — to wide acclaim at the Great American Beer Festival.
Cuvee de Tomme, Temptation and other American wild ales aren't aged in barrels for show; the wood is a vital element of fermentation. Whether spontaneously, a la Beatification, or by the addition of specific microorganisms (CdT and Temptation), these beers are "infected" with bacteria and wild yeast such as lactobacillus, pediococcus, and brettanomyces . These bugs subsequently permeate the porous wood of the barrels that the beer is aged in, with some of the organisms (like brettanomyces) actually eating the wood over time. As the barrels enter a cycle of reuse, a "house" flavor develops.
A big factor contributing to the complexity of these beers is oxidation, in which small amounts of oxygen leak through the barrels and into the beer. In wild ales, this stimulates the production of certain compounds, such as ethyl acetate, which adds depth and complexity to the beer.
Oxidation is also a major reason that "big" beers, such as imperial stouts and Belgian quadrupels, are often aged in barrels.
With their current ubiquity, it's hard to believe that Bourbon barrel-aged stouts are a product of only the last quarter-century. It was 1992 when Greg Hall of Chicago's Goose Island Beer Company first aged an imperial stout in barrels formerly containing Bourbon. The result was the infamous Bourbon County Brand Stout, which has proven to be one of the most influential beers of all time.
Unlike lambic and wild ales, which use barrels primarily as bacterial breeding grounds, Bourbon barrel-aged stouts, quads, and other big beers are generally "clean" (i.e., uninfected by bacteria or wild yeasts), using the barrels as a tool to infuse the flavor of the spirits they once held, as well as a way to introduce oxidation, which can mellow out the high levels of alcohol present in the base beers.
In addition to adding flavors of Bourbon, rum, brandy, or even tequila to the beer, oak barrels also contribute pleasant flavor compounds, such as vanillin (vanilla) and lactone (a sweet, coconut flavor), which generally complement big, dark beers quite nicely.
Whether you want to explore the sour, funky flavors of wild ales aged in old wine barrels, or the complex, spirit-driven flavors of imperial stouts and other hefty beers aged in Bourbon, rum, and other spirit barrels, you need look no further than the various local breweries constantly experimenting with these techniques.
Dunedin's 7venth Sun Brewery and St. Petersburg's Green Bench Brewing are continuing the experimentation started by Cilurzo and Arthur 15 years ago, with many interesting twists. St. Petersburg's Cycle Brewing is legendary for its barrel-aged stouts, while Tampa's Cigar City Brewing frequently releases beers aged in barrels belonging to a wide variety of spirits, such as apple brandy and dark rum. Seminole's Rapp Brewing has a great barrel-aged stout aged in Heaven Hill barrels, which pops up in the tasting room from time to time. You won't have to search very hard to find good, local barrel-aged beer.
More importantly, when you find that barrel-aged beer that you absolutely love, you'll know why you love it so much. Barrel-aged beer is much more enjoyable when you understand just how and why it tastes the way it does. — email@example.com